USR UNR 2-T220 / T220B / T221 USS UNS 2-T220 Precision Foil Resistors • • • • • • • Resistances from 0.5Ohm to 150kOhms Power Rating to 10Watt Resistance Tolerances to ±0.01% TCR to ±3ppm/K Load Stability to 0.01% TO-220 Housing Convenient SMD D2Pak Available SPECIFICATIONS Type Resistance Range Power rating free air 70°C (R<50R0) free air 70°C (R>50R0) with heatsink (R<50R0) with heatsink (R>50R0) Thermal Resistance Rthj-c R<50R0 R>50R0 Tolerances from 0.5 Ohms from 10.0 Ohms from 25.0 Ohms from 50.0 Ohms USR / USS UNR /UNS 0.5 Ohms to 150 kOhms 0.5 Ohms to 5 kOhms 1.5W 1.0W 10W 6W 1.5W 1.0W 15W 10W 10.8 K/W 18.8 K/W 6.8 K/W 10.8 K/W 0.1% / 0.25% / 0.5% / 1% 0.05% / 0.1% / 0.25% / 0.5% / 1% 0.02% / 0.05% / 0.1% / 0.25% / 0.5% / 1% 0.01% / 0.02% / 0.05% / 0.1% / 0.25% / 0.5% / 1% Stability 0.01% Shelf Life Stability 25ppm / ∆R after 1 year 50ppm / ∆R after 3 year Temperature Coefficient max. ±5ppm/K (-55 to 155°C) typ. ±3ppm/K (-55 to 125°C) Voltage Proof 1 kVDC Thermal EMF < 0.1µV/K Operating Temperature Range -55 to 155°C Resistor Material Substrate Housing Connector Material NiCr-Foil Al2O3 AlN Epoxy + Cu heatsink nickel plated Cu tinned Terminals 2 Max. Torque 1.0 Nm Notes Specially designed for applications with fast changing electrical load Ordering Information Part Description: Part Type - Resistance - Contact - Tolerance - TCR Example: UNR 2-T220B 5.7kOhms C 0.5% 3ppm Riedon Inc. 300 Cypress Avenue Alhambra CA 91801 (626) 284-9901 (626) 284-1704 www.riedon.com 06/13 USR UNR 2-T220 / T220B / T221 USS UNS 2-T220 Precision Foil Resistors SPECIFICATIONS (continued) Temperature Coefficient 800 600 +5ppm/K -5ppm/K ∆R/R (ppm) 400 200 Nominal Spread ±2.3ppm/K 0 -200 Nominal ∆R/R -400 Nominal Spread ±2.3ppm/K -600 -800 -50 -25 0 25 50 100 125 Temperature (°C) Derating Power (% from nominal power) 75 Power Rating Notes - The U-Series Resistors must be attached to a suitable heatsink. The maximum internal resistor temperature is 155°C. To specify an appropriate heatsink use the following formula : 120 100 80 RqH = TMAX - ( P x RqR ) - TA P 60 40 20 0 25 50 85 100 115 130 145 155 Temperature of the backplate(°C) Where:RqH = Thermal Resistance of Heatsink ( K/W ) RqR = Thermal Resistance of Resistor ( K/W ) TMAX = Maximum Temperature of Resistor TA = Ambient Temperature of Heatsink ( °C ) P = Power Through Resistor ( W ) Dimensions USS 2-T220 / UNS 2-T220 Dimension mm tol. (±mm) inches tol. (±inches) A 12.70 0.2 0.50 0.008 Dimension mm inches B 10.16 0.2 0.40 0.008 A 12.10 0.476 C 0.76 0.1 0.03 0.004 B 11.16 0.439 D 5.08 0.1 0.20 0.004 C 18.33 0.722 E 4.00 0.1 0.16 0.004 D 5.08 0.200 0.004 E 1.76 0.069 F 3.20 0.126 F G 1.20 0.1 0.05 14.60 0.2 0.57 0.008 H 15.00 0.2 0.59 0.008 I 17.33 0.2 0.68 0.008 J 0.40 0.1 0.02 0.004 K 1.85 0.1 0.07 0.004 Riedon Inc. 300 Cypress Avenue Alhambra CA 91801 (626) 284-9901 (626) 284-1704 www.riedon.com 06/13 USR UNR 2-T220 / T220B / T221 USS UNS 2-T220 Precision Foil Resistors SPECIFICATIONS (continued) Dimensions USR 2-T220B / UNR 2-T220B USR 2-T221 / UNR 2-T221 USR 2-T220 / UNR 2-T220 Dimension mm tol. (±mm) inches tol. (±inches) A 17.30 0.2 0.68 0.008 B 10.16 0.2 0.40 0.008 C 6.00 0.1 0.24 0.004 D Ø3.7 0.1 Ø0.146 0.004 E 16.40 0.2 0.65 0.008 F 5.08 0.1 0.20 0.004 G 0.76 0.1 0.03 0.004 H 1.30 0.1 0.05 0.004 I 10.00 0.2 0.39 0.008 I (C-Contact) 13.80 0.2 0.54 0.008 J 2.00 0.1 0.08 0.004 K 1.20 0.1 0.05 0.004 L 4.00 0.1 0.16 0.004 M 2.90 0.1 0.11 0.004 N 0.40 0.1 0.02 0.004 O 1.85 0.1 0.07 0.004 Dimension mm tol. (±mm) inches tol. (±inches) A 18.30 0.2 0.72 0.008 B 10.16 0.2 0.40 0.008 C 3.70 0.1 0.15 0.004 D Ø3.2 0.1 Ø0.126 0.004 E 16.40 0.2 0.65 0.008 F 5.08 0.1 0.20 0.004 G 0.76 0.1 0.03 0.004 H 1.30 0.1 0.05 0.004 I 10.00 0.2 0.39 0.008 I (C-Contact) 13.80 0.2 0.54 0.008 J 2.00 0.1 0.08 0.004 K 1.20 0.1 0.05 0.004 L 4.00 0.1 0.16 0.004 M 3.90 0.1 0.15 0.004 N 0.40 0.1 0.02 0.004 O 1.85 0.1 0.07 0.004 Dimension mm tol. (±mm) inches tol. (±inches) A 15.30 0.2 0.60 0.008 B 10.00 0.2 0.39 0.008 C 2.80 0.1 0.11 0.004 D Ø3.7 0.1 Ø0.146 0.004 E 2.00 0.1 0.08 0.004 F 5.08 0.1 0.20 0.004 G 1.27 0.1 0.05 0.004 H 4.60 0.1 0.18 0.004 I 6.00 0.2 0.24 0.008 J 35.30 2.0 1.39 0.079 K Ø0.6 0.1 Ø0.02 0.004 L 2.41 0.1 0.09 0.004 Riedon Inc. 300 Cypress Avenue Alhambra CA 91801 (626) 284-9901 (626) 284-1704 www.riedon.com 06/13